Monitoring & Analyzing VoIP Traffic

Voice over IP (VoIP) can provide many benefits to organizations large and small. By bringing all traffic onto a single network, businesses can realize cost savings and increase the efficiency of their communications. But before turning your organization on to the benefits of VoIP, you need to make sure your network can handle it.

When you add VoIP to the network, traffic volume rises, which can lead to problems since voice is more sensitive to network slowdowns and glitches than data. You need to assess the utilization of your network over a period of time and determine how the traffic volume on the network will affect voice applications. There are plenty of VoIP-specific traffic analysis tools and suites on the market that will allow you to do just that. And once the technology has been deployed, you can rely on the same tools, along with voice quality testers and other software, to ensure your voice network is up to par. Because there are so many tools available for assessing your network traffic, we can only cover a few of them here.

Acterna’s PVA-1000 VoIP Network Analysis Suite is based on patent-pending software that goes beyond the identification of problems to perform detailed analysis and troubleshooting, graphing jitter and packet loss to allow network admins to quickly identify problems. You can build and distribute custom Ethernet capture files, which allows you to isolate the calls with unacceptable quality. Acterna’s HST-3000 VoIP Tester is a handheld field-test tool that can be used to tune and troubleshoot VoIP deployment, allowing packet capture of live calls, including call storage and the ability to send captured calls back to the PVA-1000 software to be analyzed.

Agilent is another big name with several products that fit the bill, from network analyzer solutions to IP telephony report software and a voice quality tester. The Agilent Telephony Network Analyzer diagnoses VoIP Quality of Service (QoS) through several measurements. Expert analysis of VoIP protocols also is embedded in the tool, and it includes complete layer 1 through 7 testing over all kinds of networks. Agilent also offers a Voice Quality Tester (VQT), which tests voice quality on modern telephony networks, including VoIP, VoATM and hybrid networks. It will test for voice clarity, delay, echo, silence suppression, DTMF and signal loss.

Brix Networks offers a free voice-quality testing portal, called TestYourVoIP.com, which enables users to independently measure broadband VoIP connection quality through a quick test call, a nice little solution for individual and small business users. Brix also offers Advanced VoIP Test Suites, which test the performance of diverse VoIP applications using a standards-based, vendor-neutral approach.

Finisar’s Surveyor network Monitoring and Analysis Console is an integrated analyzer and monitoring application designed for 10/100 and 1 Gigabit Ethernet networks. It includes VoIP call quality metrics and protocol decodes with the Multi-QoS Plug-In, an add-on that enables VoIP monitoring and analysis for converged multimedia networks. It verifies QoS and service level agreement quality levels by monitoring things like jitter, drops and impairment burstiness.

If you’re into Sniffer products, very popular network analysis tools, you might just go for Sniffer Voice, an add-on package for Sniffer Portable, Sniffer Distributed and Netasyst network analyzer. It offers real-time analysis and decoding, so network administrators can ensure the highest quality voice services.

Viola Networks’ NetAlly VoIP allows pre-deployment assessments to determine whether your network is ready for VoIP, and it also provides built-in troubleshooting to help pinpoint where you need improvement before you can successfully deploy the technology. After deployment, NetAlly will continue to verify performance and diagnose problems in real time.

WildPackets, another popular provider of advanced network analysis, recently released its EtherPeek VX expert VoIP network analyzer, which combines WildPackets’ award-winning network analytics with advanced VoIP analytics. This allows network admins to troubleshoot both data and voice-related problems on their VoIP networks. This tool also can be used in all phases of deployment, from planning to ongoing maintenance. Engineers can use the objective metrics in the product to compare the performance of their network to what has been promised in SLAs. It can analyze as many as 100 open calls at the same time, and because it uses passive monitoring, it does not interfere with network performance.

For more options, check out AppareNet (which has a tool coming out this month), Avaya, Empirix Integrated Research, Ixia and others.

Emily Hollis is managing editor for Certification Magazine. She can be reached at ehollis@certmag.com.